Sent MERLIN post to here: Here's the replay pack of those games. I cut out the games that HolyHelicopter wasn't in before and after, but none of those had desyncs, and we all played at high video settings.

Game 1: HolyHelicopter desyncs very early. I worry that video settings may not be related. We decide to see if it was random, and play another.Game 2: Holy desyncs before he picks a hero. We're curious if it's his client, or something we're doing.Game 3: Holy desyncs again, and has begun to suspect that picking his abilities is what makes him desync.Game 4: A little bit of screwing around to see if we can determine what causes him to desync. I don't see anything obvious.Game 5: Holy puts no points in skills all game to see if he will still desync. It takes longer than previously, but he still does after a while.Game 6: Holy goes afk for the entire game and still desyncs. We wanted to see if it was our actions or his causing him to desync.Game 7: Holy and I do a 1v1 to see if I could make him desync. He afk'd, but there was no desync after 8 minutes, so we decided to remake.Game 8: 1v1 again, but this time we play normally. He desyns after a couple of minutes.Game 9: Holy turns his video settings down to low, just for curiousity's sake. He desyns early again.

About 99.99% sure I found the cause (and it should be an easy fix ). Cass thinks he remembers other desyncs when there weren't players doing anything (as in just sitting in base, not even casting any spells). But the one I found probably explains the vast majority of all pub desyncs since it effects non-English versions of the game.

Been checking out Merlin's old replays from the bugs topic and I can see it happening in them

Glad to hear this has finally been put to rest, though it's a shame we couldn't figure it out back in July/August of last year when there was still momentum behind the new release. Hopefully you guys will find the time to get some new versions of O out, because League of Legends just pisses me off. :\